1. Field of the Invention
Our invention relates to hydraulic torque converters, and in particular to improvements in a torque converter of the type equipped with a lock-up clutch to permit direct coupling of the converter input and output means for operation in the coupling range, that is, operation in which the torque ratio of the converter is unity.
2. Description of the Prior Art
The lock-up clutch has been used extensively in association with a hydraulic torque converter for operation above the coupling point. During operation in the coupling range, however, the reactor or stator member of the torque converter causes the hydraulic fluid medium within the converter to offer considerable obstruction to the joint rotation of the impeller and the turbine members, resulting in substantial power loss. This defect has heretofore been obviated by mounting the reactor member on a freewheeling mechanism including an overrunning or one-way clutch, which permits the reactor member to revolve freely, or "freewheel," with the fluid upon engagement of the lock-up clutch.
The reactor freewheeling mechanism, however, if expensive in construction, difficult of manufacture, and susceptible to relatively frequent trouble in use, increasing the manufacturing and maintenance costs of the torque converter. Moreover, the freewheeling mechanism for use in or with a large-capacity torque converter is inevitably of such bulk that it cannot possibly be mounted radially inwardly of the converter torus, but on its front or rear side, with the resultant increase in the axial dimension of the converter. Still further, even if the reactor member is mounted on the freewheeling mechanism, power loss arising from the turbulent flow of the fluid medium cannot be prevented completely.